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2.
J Korean Med Sci ; 35(46): e413, 2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-33258333

RESUMO

BACKGROUND: The Korean Society of Thoracic Radiology (KSTR) recently constructed a nation-wide coronavirus disease 2019 (COVID-19) database and imaging repository, referred to the Korean imaging cohort of COVID-19 (KICC-19) based on the collaborative efforts of its members. The purpose of this study was to provide a summary of the clinico-epidemiological data and imaging data of the KICC-19. METHODS: The KSTR members at 17 COVID-19 referral centers retrospectively collected imaging data and clinical information of consecutive patients with reverse transcription polymerase chain reaction-proven COVID-19 in respiratory specimens from February 2020 through May 2020 who underwent diagnostic chest computed tomography (CT) or radiograph in each participating hospital. RESULTS: The cohort consisted of 239 men and 283 women (mean age, 52.3 years; age range, 11-97 years). Of the 522 subjects, 201 (38.5%) had an underlying disease. The most common symptoms were fever (n = 292) and cough (n = 245). The 151 patients (28.9%) had lymphocytopenia, 86 had (16.5%) thrombocytopenia, and 227 patients (43.5%) had an elevated CRP at admission. The 121 (23.4%) needed nasal oxygen therapy or mechanical ventilation (n = 38; 7.3%), and 49 patients (9.4%) were admitted to an intensive care unit. Although most patients had cured, 21 patients (4.0%) died. The 465 (89.1%) subjects underwent a low to standard-dose chest CT scan at least once during hospitalization, resulting in a total of 658 CT scans. The 497 subjects (95.2%) underwent chest radiography at least once during hospitalization, which resulted in a total of 1,475 chest radiographs. CONCLUSION: The KICC-19 was successfully established and comprised of 658 CT scans and 1,475 chest radiographs of 522 hospitalized Korean COVID-19 patients. The KICC-19 will provide a more comprehensive understanding of the clinical, epidemiological, and radiologic characteristics of patients with COVID-19.


Assuntos
COVID-19/diagnóstico por imagem , Radiografia Torácica/métodos , SARS-CoV-2 , Tomografia Computadorizada por Raios X/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , COVID-19/terapia , Criança , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
3.
Acta Radiol ; 56(12): 1463-70, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25406431

RESUMO

BACKGROUND: Previous studies have correlated the maximum standardized uptake value (SUVmax) of breast cancer lesions with histological and biological characteristics such as tumor size, histologic grade, or hormonal receptor expression status. However, controversy remains concerning the prognostic value of SUVmax in breast cancer. PURPOSE: To determine if the SUVmax of a tumor on 18F-fluorodeoxyglucose positron emission tomography (18F-FDG PET) is associated with disease-free survival in patients with primary invasive ductal breast cancer. MATERIAL AND METHODS: The institutional review board of our hospital approved this retrospective study. From 2009 to 2011, 508 women (mean age, 53.6 years; age range, 26-85 years) with newly diagnosed invasive ductal breast cancer who had undergone preoperative 18F-FDG PET/CT followed by surgery were identified. Clinicopathological variables and FDG uptake quantified by SUVmax were analyzed. The Cox proportional hazards model was used to evaluate the association between SUVmax and disease-free survival after controlling for clinicopathological parameters. RESULTS: There were 21 recurrences at a median follow-up of 46 months. The mean SUVmax of the primary tumor was significantly higher in patients with a recurrence than those who remained disease-free (9.5 ± 3.5 vs. 6.6 ± 4.2, P < 0.001). A receiver operating characteristic curve indicated that a SUVmax of 5.95 was the optimal cut-off value to predict disease-free survival. Multivariate analysis identified a high SUVmax (≥5.95) and high T stage as independent significant variables associated with worse disease-free survival. CONCLUSION: A high primary tumor SUVmax on 18F-FDG PET/CT was an independent factor associated with worse disease-free survival in patients with primary invasive ductal breast cancer.


Assuntos
Neoplasias da Mama/diagnóstico , Carcinoma Ductal de Mama/diagnóstico , Fluordesoxiglucose F18 , Tomografia por Emissão de Pósitrons , Cuidados Pré-Operatórios , Tomografia Computadorizada por Raios X , Adulto , Idoso , Idoso de 80 Anos ou mais , Mama/diagnóstico por imagem , Intervalo Livre de Doença , Feminino , Humanos , Mamografia , Pessoa de Meia-Idade , Imagem Multimodal , Valor Preditivo dos Testes , Modelos de Riscos Proporcionais , Compostos Radiofarmacêuticos , Reprodutibilidade dos Testes , Estudos Retrospectivos
4.
Arch Pharm Res ; 37(11): 1437-44, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24293061

RESUMO

In order to optimize the extraction conditions of continentalic acid, the main compound from Aralia continentalis root, we developed a model using the response surface methodology. The continentalic acid yield was analyzed and quantified by high-performance liquid chromatography coupled with UV detection. The extraction solvent, temperature, and time the three main factors for ultrasound-assisted extraction were optimized using the central composite design. Analysis of variance showed a good model fit (R (2) = 0.9323). The maximum extraction of continentalic acid obtained experimentally was 1.0138 % under an extraction temperature of 33 °C and extraction time of 28 min when 100 % ethanol was used as the solvent. The experimental value was in good agreement (the yield 1.0103 %) with those predicted values. The results clearly showed that quality by statistical design could be effectively applied to optimize extraction of continentalic acid.


Assuntos
Aralia/química , Diterpenos/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Sonicação/métodos , Cromatografia Líquida de Alta Pressão , Estrutura Molecular , Raízes de Plantas/química , Solventes/química , Espectrometria de Massas por Ionização por Electrospray
5.
Biotechnol Bioeng ; 104(4): 729-39, 2009 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-19575416

RESUMO

3-Hydroxypropionic acid (3-HP) is a commercially valuable chemical with the potential to be a key building block for deriving many industrially important chemicals. However, its biological production has not been well documented. Our previous study demonstrated the feasibility of producing 3-HP from glycerol using the recombinant Escherichia coli SH254 expressing glycerol dehydratase (DhaB) and aldehyde dehydrogenase (AldH), and reported that an "imbalance between the two enzymes" and the "instability of the first enzyme DhaB" were the major factors limiting 3-HP production. In this study, the efficiency of the recombinant strain(s) was improved by expressing DhaB and AldH in two compatible isopropyl-thio-beta-galactoside (IPTG) inducible plasmids along with glycerol dehydratase reactivase (GDR). The expression levels of the two proteins were measured. It was found that the changes in protein expression were associated with their enzymatic activity and balance. While cloning an alternate aldehyde dehydrogenase (ALDH), alpha-ketoglutaric semialdehyde dehydrogenase (KGSADH), instead of AldH, the recombinant E. coli SH-BGK1 showed the highest level of 3-HP production (2.8 g/L) under shake-flask conditions. When an aerobic fed-batch process was carried out under bioreactor conditions at pH 7.0, the recombinant SH-BGK1 produced 38.7 g 3-HP/L with an average yield of 35%. This article reports the highest level of 3-HP production from glycerol thus far.


Assuntos
Vias Biossintéticas/genética , Escherichia coli/genética , Escherichia coli/metabolismo , Engenharia Genética , Glicerol/metabolismo , Ácido Láctico/análogos & derivados , Aldeído Desidrogenase/genética , Aldeído Desidrogenase/metabolismo , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Expressão Gênica , Regulação Bacteriana da Expressão Gênica , Hidroliases/genética , Hidroliases/metabolismo , Ácido Láctico/biossíntese , Plasmídeos , Regiões Promotoras Genéticas , Recombinação Genética
6.
Appl Microbiol Biotechnol ; 81(1): 51-60, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18668238

RESUMO

3-Hydroxypropionaldehyde (3-HPA), an intermediary compound of glycerol metabolism in bacteria, serves as a precursor to 3-Hydroxypropionic acid (3-HP), a commercially valuable platform chemical. To achieve the effective conversion of 3-HPA to 3-HP, an aldH gene encoding an aldehyde dehydrogenase in Escherichia coli K-12 (AldH) was cloned, expressed, and characterized for its properties. The recombinant AldH exhibited broad substrate specificity for various aliphatic and aromatic aldehydes. AldH preferred NAD+ over NADP+ as a cofactor for the oxidation of most aliphatic aldehydes tested. Among the aldehydes used, the specific activity was highest (38.1 U mg(-1) protein) for 3-HPA at pH 8.0 and 37 degrees C. The catalytic efficiency (kcat) and the specificity constant (kcat/Km) for 3-HPA in the presence of NAD+ were 28.5 s(-1) and 58.6x10(3) M(-1) s(-1), respectively. The AldH activity was enhanced in the presence of disulfide reductants such as dithiothreitol (DTT) or 2-mercaptoethanol, while several metal ions, particularly Hg2+, Ag+, Cu2+, and Zn2+, inhibited AldH activity. This study illustrates that AldH is a potentially useful enzyme in converting 3-HPA to 3-HP.


Assuntos
Aldeído Desidrogenase/química , Clonagem Molecular , Escherichia coli K12/enzimologia , Proteínas de Escherichia coli/química , Expressão Gênica , Gliceraldeído/análogos & derivados , Propano/metabolismo , Aldeído Desidrogenase/genética , Aldeído Desidrogenase/isolamento & purificação , Aldeído Desidrogenase/metabolismo , Sequência de Aminoácidos , Coenzimas/metabolismo , Estabilidade Enzimática , Escherichia coli K12/química , Escherichia coli K12/genética , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/isolamento & purificação , Proteínas de Escherichia coli/metabolismo , Gliceraldeído/metabolismo , Cinética , Ácido Láctico/análogos & derivados , Ácido Láctico/metabolismo , Dados de Sequência Molecular , Homologia de Sequência de Aminoácidos , Especificidade por Substrato
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